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<pre><span class="sourceLineNo">001</span>/*<a name="line.1"></a>
<span class="sourceLineNo">002</span> * Copyright (C) 2007 The Guava Authors<a name="line.2"></a>
<span class="sourceLineNo">003</span> *<a name="line.3"></a>
<span class="sourceLineNo">004</span> * Licensed under the Apache License, Version 2.0 (the "License");<a name="line.4"></a>
<span class="sourceLineNo">005</span> * you may not use this file except in compliance with the License.<a name="line.5"></a>
<span class="sourceLineNo">006</span> * You may obtain a copy of the License at<a name="line.6"></a>
<span class="sourceLineNo">007</span> *<a name="line.7"></a>
<span class="sourceLineNo">008</span> * http://www.apache.org/licenses/LICENSE-2.0<a name="line.8"></a>
<span class="sourceLineNo">009</span> *<a name="line.9"></a>
<span class="sourceLineNo">010</span> * Unless required by applicable law or agreed to in writing, software<a name="line.10"></a>
<span class="sourceLineNo">011</span> * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.11"></a>
<span class="sourceLineNo">012</span> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.12"></a>
<span class="sourceLineNo">013</span> * See the License for the specific language governing permissions and<a name="line.13"></a>
<span class="sourceLineNo">014</span> * limitations under the License.<a name="line.14"></a>
<span class="sourceLineNo">015</span> */<a name="line.15"></a>
<span class="sourceLineNo">016</span><a name="line.16"></a>
<span class="sourceLineNo">017</span>package com.google.common.collect;<a name="line.17"></a>
<span class="sourceLineNo">018</span><a name="line.18"></a>
<span class="sourceLineNo">019</span>import static com.google.common.base.Preconditions.checkArgument;<a name="line.19"></a>
<span class="sourceLineNo">020</span>import static com.google.common.base.Preconditions.checkNotNull;<a name="line.20"></a>
<span class="sourceLineNo">021</span><a name="line.21"></a>
<span class="sourceLineNo">022</span>import com.google.common.annotations.Beta;<a name="line.22"></a>
<span class="sourceLineNo">023</span>import com.google.common.annotations.GwtCompatible;<a name="line.23"></a>
<span class="sourceLineNo">024</span>import com.google.common.annotations.GwtIncompatible;<a name="line.24"></a>
<span class="sourceLineNo">025</span>import com.google.common.base.Predicate;<a name="line.25"></a>
<span class="sourceLineNo">026</span>import com.google.common.base.Predicates;<a name="line.26"></a>
<span class="sourceLineNo">027</span>import com.google.common.collect.Collections2.FilteredCollection;<a name="line.27"></a>
<span class="sourceLineNo">028</span><a name="line.28"></a>
<span class="sourceLineNo">029</span>import java.io.IOException;<a name="line.29"></a>
<span class="sourceLineNo">030</span>import java.io.ObjectInputStream;<a name="line.30"></a>
<span class="sourceLineNo">031</span>import java.io.Serializable;<a name="line.31"></a>
<span class="sourceLineNo">032</span>import java.util.AbstractSet;<a name="line.32"></a>
<span class="sourceLineNo">033</span>import java.util.Arrays;<a name="line.33"></a>
<span class="sourceLineNo">034</span>import java.util.Collection;<a name="line.34"></a>
<span class="sourceLineNo">035</span>import java.util.Collections;<a name="line.35"></a>
<span class="sourceLineNo">036</span>import java.util.Comparator;<a name="line.36"></a>
<span class="sourceLineNo">037</span>import java.util.EnumSet;<a name="line.37"></a>
<span class="sourceLineNo">038</span>import java.util.HashSet;<a name="line.38"></a>
<span class="sourceLineNo">039</span>import java.util.Iterator;<a name="line.39"></a>
<span class="sourceLineNo">040</span>import java.util.LinkedHashSet;<a name="line.40"></a>
<span class="sourceLineNo">041</span>import java.util.List;<a name="line.41"></a>
<span class="sourceLineNo">042</span>import java.util.Map;<a name="line.42"></a>
<span class="sourceLineNo">043</span>import java.util.NavigableSet;<a name="line.43"></a>
<span class="sourceLineNo">044</span>import java.util.NoSuchElementException;<a name="line.44"></a>
<span class="sourceLineNo">045</span>import java.util.Set;<a name="line.45"></a>
<span class="sourceLineNo">046</span>import java.util.SortedSet;<a name="line.46"></a>
<span class="sourceLineNo">047</span>import java.util.TreeSet;<a name="line.47"></a>
<span class="sourceLineNo">048</span>import java.util.concurrent.CopyOnWriteArraySet;<a name="line.48"></a>
<span class="sourceLineNo">049</span><a name="line.49"></a>
<span class="sourceLineNo">050</span>import javax.annotation.Nullable;<a name="line.50"></a>
<span class="sourceLineNo">051</span><a name="line.51"></a>
<span class="sourceLineNo">052</span>/**<a name="line.52"></a>
<span class="sourceLineNo">053</span> * Static utility methods pertaining to {@link Set} instances. Also see this<a name="line.53"></a>
<span class="sourceLineNo">054</span> * class's counterparts {@link Lists}, {@link Maps} and {@link Queues}.<a name="line.54"></a>
<span class="sourceLineNo">055</span> *<a name="line.55"></a>
<span class="sourceLineNo">056</span> * &lt;p&gt;See the Guava User Guide article on &lt;a href=<a name="line.56"></a>
<span class="sourceLineNo">057</span> * "http://code.google.com/p/guava-libraries/wiki/CollectionUtilitiesExplained#Sets"&gt;<a name="line.57"></a>
<span class="sourceLineNo">058</span> * {@code Sets}&lt;/a&gt;.<a name="line.58"></a>
<span class="sourceLineNo">059</span> *<a name="line.59"></a>
<span class="sourceLineNo">060</span> * @author Kevin Bourrillion<a name="line.60"></a>
<span class="sourceLineNo">061</span> * @author Jared Levy<a name="line.61"></a>
<span class="sourceLineNo">062</span> * @author Chris Povirk<a name="line.62"></a>
<span class="sourceLineNo">063</span> * @since 2.0 (imported from Google Collections Library)<a name="line.63"></a>
<span class="sourceLineNo">064</span> */<a name="line.64"></a>
<span class="sourceLineNo">065</span>@GwtCompatible(emulated = true)<a name="line.65"></a>
<span class="sourceLineNo">066</span>public final class Sets {<a name="line.66"></a>
<span class="sourceLineNo">067</span>  private Sets() {}<a name="line.67"></a>
<span class="sourceLineNo">068</span><a name="line.68"></a>
<span class="sourceLineNo">069</span>  /**<a name="line.69"></a>
<span class="sourceLineNo">070</span>   * {@link AbstractSet} substitute without the potentially-quadratic<a name="line.70"></a>
<span class="sourceLineNo">071</span>   * {@code removeAll} implementation.<a name="line.71"></a>
<span class="sourceLineNo">072</span>   */<a name="line.72"></a>
<span class="sourceLineNo">073</span>  abstract static class ImprovedAbstractSet&lt;E&gt; extends AbstractSet&lt;E&gt; {<a name="line.73"></a>
<span class="sourceLineNo">074</span>    @Override<a name="line.74"></a>
<span class="sourceLineNo">075</span>    public boolean removeAll(Collection&lt;?&gt; c) {<a name="line.75"></a>
<span class="sourceLineNo">076</span>      return removeAllImpl(this, c);<a name="line.76"></a>
<span class="sourceLineNo">077</span>    }<a name="line.77"></a>
<span class="sourceLineNo">078</span><a name="line.78"></a>
<span class="sourceLineNo">079</span>    @Override<a name="line.79"></a>
<span class="sourceLineNo">080</span>    public boolean retainAll(Collection&lt;?&gt; c) {<a name="line.80"></a>
<span class="sourceLineNo">081</span>      return super.retainAll(checkNotNull(c)); // GWT compatibility<a name="line.81"></a>
<span class="sourceLineNo">082</span>    }<a name="line.82"></a>
<span class="sourceLineNo">083</span>  }<a name="line.83"></a>
<span class="sourceLineNo">084</span><a name="line.84"></a>
<span class="sourceLineNo">085</span>  /**<a name="line.85"></a>
<span class="sourceLineNo">086</span>   * Returns an immutable set instance containing the given enum elements.<a name="line.86"></a>
<span class="sourceLineNo">087</span>   * Internally, the returned set will be backed by an {@link EnumSet}.<a name="line.87"></a>
<span class="sourceLineNo">088</span>   *<a name="line.88"></a>
<span class="sourceLineNo">089</span>   * &lt;p&gt;The iteration order of the returned set follows the enum's iteration<a name="line.89"></a>
<span class="sourceLineNo">090</span>   * order, not the order in which the elements are provided to the method.<a name="line.90"></a>
<span class="sourceLineNo">091</span>   *<a name="line.91"></a>
<span class="sourceLineNo">092</span>   * @param anElement one of the elements the set should contain<a name="line.92"></a>
<span class="sourceLineNo">093</span>   * @param otherElements the rest of the elements the set should contain<a name="line.93"></a>
<span class="sourceLineNo">094</span>   * @return an immutable set containing those elements, minus duplicates<a name="line.94"></a>
<span class="sourceLineNo">095</span>   */<a name="line.95"></a>
<span class="sourceLineNo">096</span>  // http://code.google.com/p/google-web-toolkit/issues/detail?id=3028<a name="line.96"></a>
<span class="sourceLineNo">097</span>  @GwtCompatible(serializable = true)<a name="line.97"></a>
<span class="sourceLineNo">098</span>  public static &lt;E extends Enum&lt;E&gt;&gt; ImmutableSet&lt;E&gt; immutableEnumSet(<a name="line.98"></a>
<span class="sourceLineNo">099</span>      E anElement, E... otherElements) {<a name="line.99"></a>
<span class="sourceLineNo">100</span>    return ImmutableEnumSet.asImmutable(EnumSet.of(anElement, otherElements));<a name="line.100"></a>
<span class="sourceLineNo">101</span>  }<a name="line.101"></a>
<span class="sourceLineNo">102</span><a name="line.102"></a>
<span class="sourceLineNo">103</span>  /**<a name="line.103"></a>
<span class="sourceLineNo">104</span>   * Returns an immutable set instance containing the given enum elements.<a name="line.104"></a>
<span class="sourceLineNo">105</span>   * Internally, the returned set will be backed by an {@link EnumSet}.<a name="line.105"></a>
<span class="sourceLineNo">106</span>   *<a name="line.106"></a>
<span class="sourceLineNo">107</span>   * &lt;p&gt;The iteration order of the returned set follows the enum's iteration<a name="line.107"></a>
<span class="sourceLineNo">108</span>   * order, not the order in which the elements appear in the given collection.<a name="line.108"></a>
<span class="sourceLineNo">109</span>   *<a name="line.109"></a>
<span class="sourceLineNo">110</span>   * @param elements the elements, all of the same {@code enum} type, that the<a name="line.110"></a>
<span class="sourceLineNo">111</span>   *     set should contain<a name="line.111"></a>
<span class="sourceLineNo">112</span>   * @return an immutable set containing those elements, minus duplicates<a name="line.112"></a>
<span class="sourceLineNo">113</span>   */<a name="line.113"></a>
<span class="sourceLineNo">114</span>  // http://code.google.com/p/google-web-toolkit/issues/detail?id=3028<a name="line.114"></a>
<span class="sourceLineNo">115</span>  @GwtCompatible(serializable = true)<a name="line.115"></a>
<span class="sourceLineNo">116</span>  public static &lt;E extends Enum&lt;E&gt;&gt; ImmutableSet&lt;E&gt; immutableEnumSet(<a name="line.116"></a>
<span class="sourceLineNo">117</span>      Iterable&lt;E&gt; elements) {<a name="line.117"></a>
<span class="sourceLineNo">118</span>    if (elements instanceof ImmutableEnumSet) {<a name="line.118"></a>
<span class="sourceLineNo">119</span>      return (ImmutableEnumSet&lt;E&gt;) elements;<a name="line.119"></a>
<span class="sourceLineNo">120</span>    } else if (elements instanceof Collection) {<a name="line.120"></a>
<span class="sourceLineNo">121</span>      Collection&lt;E&gt; collection = (Collection&lt;E&gt;) elements;<a name="line.121"></a>
<span class="sourceLineNo">122</span>      if (collection.isEmpty()) {<a name="line.122"></a>
<span class="sourceLineNo">123</span>        return ImmutableSet.of();<a name="line.123"></a>
<span class="sourceLineNo">124</span>      } else {<a name="line.124"></a>
<span class="sourceLineNo">125</span>        return ImmutableEnumSet.asImmutable(EnumSet.copyOf(collection));<a name="line.125"></a>
<span class="sourceLineNo">126</span>      }<a name="line.126"></a>
<span class="sourceLineNo">127</span>    } else {<a name="line.127"></a>
<span class="sourceLineNo">128</span>      Iterator&lt;E&gt; itr = elements.iterator();<a name="line.128"></a>
<span class="sourceLineNo">129</span>      if (itr.hasNext()) {<a name="line.129"></a>
<span class="sourceLineNo">130</span>        EnumSet&lt;E&gt; enumSet = EnumSet.of(itr.next());<a name="line.130"></a>
<span class="sourceLineNo">131</span>        Iterators.addAll(enumSet, itr);<a name="line.131"></a>
<span class="sourceLineNo">132</span>        return ImmutableEnumSet.asImmutable(enumSet);<a name="line.132"></a>
<span class="sourceLineNo">133</span>      } else {<a name="line.133"></a>
<span class="sourceLineNo">134</span>        return ImmutableSet.of();<a name="line.134"></a>
<span class="sourceLineNo">135</span>      }<a name="line.135"></a>
<span class="sourceLineNo">136</span>    }<a name="line.136"></a>
<span class="sourceLineNo">137</span>  }<a name="line.137"></a>
<span class="sourceLineNo">138</span><a name="line.138"></a>
<span class="sourceLineNo">139</span>  /**<a name="line.139"></a>
<span class="sourceLineNo">140</span>   * Returns a new {@code EnumSet} instance containing the given elements.<a name="line.140"></a>
<span class="sourceLineNo">141</span>   * Unlike {@link EnumSet#copyOf(Collection)}, this method does not produce an<a name="line.141"></a>
<span class="sourceLineNo">142</span>   * exception on an empty collection, and it may be called on any iterable, not<a name="line.142"></a>
<span class="sourceLineNo">143</span>   * just a {@code Collection}.<a name="line.143"></a>
<span class="sourceLineNo">144</span>   */<a name="line.144"></a>
<span class="sourceLineNo">145</span>  public static &lt;E extends Enum&lt;E&gt;&gt; EnumSet&lt;E&gt; newEnumSet(Iterable&lt;E&gt; iterable,<a name="line.145"></a>
<span class="sourceLineNo">146</span>      Class&lt;E&gt; elementType) {<a name="line.146"></a>
<span class="sourceLineNo">147</span>    EnumSet&lt;E&gt; set = EnumSet.noneOf(elementType);<a name="line.147"></a>
<span class="sourceLineNo">148</span>    Iterables.addAll(set, iterable);<a name="line.148"></a>
<span class="sourceLineNo">149</span>    return set;<a name="line.149"></a>
<span class="sourceLineNo">150</span>  }<a name="line.150"></a>
<span class="sourceLineNo">151</span><a name="line.151"></a>
<span class="sourceLineNo">152</span>  // HashSet<a name="line.152"></a>
<span class="sourceLineNo">153</span><a name="line.153"></a>
<span class="sourceLineNo">154</span>  /**<a name="line.154"></a>
<span class="sourceLineNo">155</span>   * Creates a &lt;i&gt;mutable&lt;/i&gt;, empty {@code HashSet} instance.<a name="line.155"></a>
<span class="sourceLineNo">156</span>   *<a name="line.156"></a>
<span class="sourceLineNo">157</span>   * &lt;p&gt;&lt;b&gt;Note:&lt;/b&gt; if mutability is not required, use {@link<a name="line.157"></a>
<span class="sourceLineNo">158</span>   * ImmutableSet#of()} instead.<a name="line.158"></a>
<span class="sourceLineNo">159</span>   *<a name="line.159"></a>
<span class="sourceLineNo">160</span>   * &lt;p&gt;&lt;b&gt;Note:&lt;/b&gt; if {@code E} is an {@link Enum} type, use {@link<a name="line.160"></a>
<span class="sourceLineNo">161</span>   * EnumSet#noneOf} instead.<a name="line.161"></a>
<span class="sourceLineNo">162</span>   *<a name="line.162"></a>
<span class="sourceLineNo">163</span>   * @return a new, empty {@code HashSet}<a name="line.163"></a>
<span class="sourceLineNo">164</span>   */<a name="line.164"></a>
<span class="sourceLineNo">165</span>  public static &lt;E&gt; HashSet&lt;E&gt; newHashSet() {<a name="line.165"></a>
<span class="sourceLineNo">166</span>    return new HashSet&lt;E&gt;();<a name="line.166"></a>
<span class="sourceLineNo">167</span>  }<a name="line.167"></a>
<span class="sourceLineNo">168</span><a name="line.168"></a>
<span class="sourceLineNo">169</span>  /**<a name="line.169"></a>
<span class="sourceLineNo">170</span>   * Creates a &lt;i&gt;mutable&lt;/i&gt; {@code HashSet} instance containing the given<a name="line.170"></a>
<span class="sourceLineNo">171</span>   * elements in unspecified order.<a name="line.171"></a>
<span class="sourceLineNo">172</span>   *<a name="line.172"></a>
<span class="sourceLineNo">173</span>   * &lt;p&gt;&lt;b&gt;Note:&lt;/b&gt; if mutability is not required and the elements are<a name="line.173"></a>
<span class="sourceLineNo">174</span>   * non-null, use an overload of {@link ImmutableSet#of()} (for varargs) or<a name="line.174"></a>
<span class="sourceLineNo">175</span>   * {@link ImmutableSet#copyOf(Object[])} (for an array) instead.<a name="line.175"></a>
<span class="sourceLineNo">176</span>   *<a name="line.176"></a>
<span class="sourceLineNo">177</span>   * &lt;p&gt;&lt;b&gt;Note:&lt;/b&gt; if {@code E} is an {@link Enum} type, use {@link<a name="line.177"></a>
<span class="sourceLineNo">178</span>   * EnumSet#of(Enum, Enum[])} instead.<a name="line.178"></a>
<span class="sourceLineNo">179</span>   *<a name="line.179"></a>
<span class="sourceLineNo">180</span>   * @param elements the elements that the set should contain<a name="line.180"></a>
<span class="sourceLineNo">181</span>   * @return a new {@code HashSet} containing those elements (minus duplicates)<a name="line.181"></a>
<span class="sourceLineNo">182</span>   */<a name="line.182"></a>
<span class="sourceLineNo">183</span>  public static &lt;E&gt; HashSet&lt;E&gt; newHashSet(E... elements) {<a name="line.183"></a>
<span class="sourceLineNo">184</span>    HashSet&lt;E&gt; set = newHashSetWithExpectedSize(elements.length);<a name="line.184"></a>
<span class="sourceLineNo">185</span>    Collections.addAll(set, elements);<a name="line.185"></a>
<span class="sourceLineNo">186</span>    return set;<a name="line.186"></a>
<span class="sourceLineNo">187</span>  }<a name="line.187"></a>
<span class="sourceLineNo">188</span><a name="line.188"></a>
<span class="sourceLineNo">189</span>  /**<a name="line.189"></a>
<span class="sourceLineNo">190</span>   * Creates a {@code HashSet} instance, with a high enough "initial capacity"<a name="line.190"></a>
<span class="sourceLineNo">191</span>   * that it &lt;i&gt;should&lt;/i&gt; hold {@code expectedSize} elements without growth.<a name="line.191"></a>
<span class="sourceLineNo">192</span>   * This behavior cannot be broadly guaranteed, but it is observed to be true<a name="line.192"></a>
<span class="sourceLineNo">193</span>   * for OpenJDK 1.6. It also can't be guaranteed that the method isn't<a name="line.193"></a>
<span class="sourceLineNo">194</span>   * inadvertently &lt;i&gt;oversizing&lt;/i&gt; the returned set.<a name="line.194"></a>
<span class="sourceLineNo">195</span>   *<a name="line.195"></a>
<span class="sourceLineNo">196</span>   * @param expectedSize the number of elements you expect to add to the<a name="line.196"></a>
<span class="sourceLineNo">197</span>   *        returned set<a name="line.197"></a>
<span class="sourceLineNo">198</span>   * @return a new, empty {@code HashSet} with enough capacity to hold {@code<a name="line.198"></a>
<span class="sourceLineNo">199</span>   *         expectedSize} elements without resizing<a name="line.199"></a>
<span class="sourceLineNo">200</span>   * @throws IllegalArgumentException if {@code expectedSize} is negative<a name="line.200"></a>
<span class="sourceLineNo">201</span>   */<a name="line.201"></a>
<span class="sourceLineNo">202</span>  public static &lt;E&gt; HashSet&lt;E&gt; newHashSetWithExpectedSize(int expectedSize) {<a name="line.202"></a>
<span class="sourceLineNo">203</span>    return new HashSet&lt;E&gt;(Maps.capacity(expectedSize));<a name="line.203"></a>
<span class="sourceLineNo">204</span>  }<a name="line.204"></a>
<span class="sourceLineNo">205</span><a name="line.205"></a>
<span class="sourceLineNo">206</span>  /**<a name="line.206"></a>
<span class="sourceLineNo">207</span>   * Creates a &lt;i&gt;mutable&lt;/i&gt; {@code HashSet} instance containing the given<a name="line.207"></a>
<span class="sourceLineNo">208</span>   * elements in unspecified order.<a name="line.208"></a>
<span class="sourceLineNo">209</span>   *<a name="line.209"></a>
<span class="sourceLineNo">210</span>   * &lt;p&gt;&lt;b&gt;Note:&lt;/b&gt; if mutability is not required and the elements are<a name="line.210"></a>
<span class="sourceLineNo">211</span>   * non-null, use {@link ImmutableSet#copyOf(Iterable)} instead.<a name="line.211"></a>
<span class="sourceLineNo">212</span>   *<a name="line.212"></a>
<span class="sourceLineNo">213</span>   * &lt;p&gt;&lt;b&gt;Note:&lt;/b&gt; if {@code E} is an {@link Enum} type, use<a name="line.213"></a>
<span class="sourceLineNo">214</span>   * {@link #newEnumSet(Iterable, Class)} instead.<a name="line.214"></a>
<span class="sourceLineNo">215</span>   *<a name="line.215"></a>
<span class="sourceLineNo">216</span>   * @param elements the elements that the set should contain<a name="line.216"></a>
<span class="sourceLineNo">217</span>   * @return a new {@code HashSet} containing those elements (minus duplicates)<a name="line.217"></a>
<span class="sourceLineNo">218</span>   */<a name="line.218"></a>
<span class="sourceLineNo">219</span>  public static &lt;E&gt; HashSet&lt;E&gt; newHashSet(Iterable&lt;? extends E&gt; elements) {<a name="line.219"></a>
<span class="sourceLineNo">220</span>    return (elements instanceof Collection)<a name="line.220"></a>
<span class="sourceLineNo">221</span>        ? new HashSet&lt;E&gt;(Collections2.cast(elements))<a name="line.221"></a>
<span class="sourceLineNo">222</span>        : newHashSet(elements.iterator());<a name="line.222"></a>
<span class="sourceLineNo">223</span>  }<a name="line.223"></a>
<span class="sourceLineNo">224</span><a name="line.224"></a>
<span class="sourceLineNo">225</span>  /**<a name="line.225"></a>
<span class="sourceLineNo">226</span>   * Creates a &lt;i&gt;mutable&lt;/i&gt; {@code HashSet} instance containing the given<a name="line.226"></a>
<span class="sourceLineNo">227</span>   * elements in unspecified order.<a name="line.227"></a>
<span class="sourceLineNo">228</span>   *<a name="line.228"></a>
<span class="sourceLineNo">229</span>   * &lt;p&gt;&lt;b&gt;Note:&lt;/b&gt; if mutability is not required and the elements are<a name="line.229"></a>
<span class="sourceLineNo">230</span>   * non-null, use {@link ImmutableSet#copyOf(Iterable)} instead.<a name="line.230"></a>
<span class="sourceLineNo">231</span>   *<a name="line.231"></a>
<span class="sourceLineNo">232</span>   * &lt;p&gt;&lt;b&gt;Note:&lt;/b&gt; if {@code E} is an {@link Enum} type, you should create an<a name="line.232"></a>
<span class="sourceLineNo">233</span>   * {@link EnumSet} instead.<a name="line.233"></a>
<span class="sourceLineNo">234</span>   *<a name="line.234"></a>
<span class="sourceLineNo">235</span>   * @param elements the elements that the set should contain<a name="line.235"></a>
<span class="sourceLineNo">236</span>   * @return a new {@code HashSet} containing those elements (minus duplicates)<a name="line.236"></a>
<span class="sourceLineNo">237</span>   */<a name="line.237"></a>
<span class="sourceLineNo">238</span>  public static &lt;E&gt; HashSet&lt;E&gt; newHashSet(Iterator&lt;? extends E&gt; elements) {<a name="line.238"></a>
<span class="sourceLineNo">239</span>    HashSet&lt;E&gt; set = newHashSet();<a name="line.239"></a>
<span class="sourceLineNo">240</span>    while (elements.hasNext()) {<a name="line.240"></a>
<span class="sourceLineNo">241</span>      set.add(elements.next());<a name="line.241"></a>
<span class="sourceLineNo">242</span>    }<a name="line.242"></a>
<span class="sourceLineNo">243</span>    return set;<a name="line.243"></a>
<span class="sourceLineNo">244</span>  }<a name="line.244"></a>
<span class="sourceLineNo">245</span><a name="line.245"></a>
<span class="sourceLineNo">246</span>  // LinkedHashSet<a name="line.246"></a>
<span class="sourceLineNo">247</span><a name="line.247"></a>
<span class="sourceLineNo">248</span>  /**<a name="line.248"></a>
<span class="sourceLineNo">249</span>   * Creates a &lt;i&gt;mutable&lt;/i&gt;, empty {@code LinkedHashSet} instance.<a name="line.249"></a>
<span class="sourceLineNo">250</span>   *<a name="line.250"></a>
<span class="sourceLineNo">251</span>   * &lt;p&gt;&lt;b&gt;Note:&lt;/b&gt; if mutability is not required, use {@link<a name="line.251"></a>
<span class="sourceLineNo">252</span>   * ImmutableSet#of()} instead.<a name="line.252"></a>
<span class="sourceLineNo">253</span>   *<a name="line.253"></a>
<span class="sourceLineNo">254</span>   * @return a new, empty {@code LinkedHashSet}<a name="line.254"></a>
<span class="sourceLineNo">255</span>   */<a name="line.255"></a>
<span class="sourceLineNo">256</span>  public static &lt;E&gt; LinkedHashSet&lt;E&gt; newLinkedHashSet() {<a name="line.256"></a>
<span class="sourceLineNo">257</span>    return new LinkedHashSet&lt;E&gt;();<a name="line.257"></a>
<span class="sourceLineNo">258</span>  }<a name="line.258"></a>
<span class="sourceLineNo">259</span><a name="line.259"></a>
<span class="sourceLineNo">260</span>  /**<a name="line.260"></a>
<span class="sourceLineNo">261</span>   * Creates a {@code LinkedHashSet} instance, with a high enough "initial<a name="line.261"></a>
<span class="sourceLineNo">262</span>   * capacity" that it &lt;i&gt;should&lt;/i&gt; hold {@code expectedSize} elements without<a name="line.262"></a>
<span class="sourceLineNo">263</span>   * growth. This behavior cannot be broadly guaranteed, but it is observed to<a name="line.263"></a>
<span class="sourceLineNo">264</span>   * be true for OpenJDK 1.6. It also can't be guaranteed that the method isn't<a name="line.264"></a>
<span class="sourceLineNo">265</span>   * inadvertently &lt;i&gt;oversizing&lt;/i&gt; the returned set.<a name="line.265"></a>
<span class="sourceLineNo">266</span>   *<a name="line.266"></a>
<span class="sourceLineNo">267</span>   * @param expectedSize the number of elements you expect to add to the<a name="line.267"></a>
<span class="sourceLineNo">268</span>   *        returned set<a name="line.268"></a>
<span class="sourceLineNo">269</span>   * @return a new, empty {@code LinkedHashSet} with enough capacity to hold<a name="line.269"></a>
<span class="sourceLineNo">270</span>   *         {@code expectedSize} elements without resizing<a name="line.270"></a>
<span class="sourceLineNo">271</span>   * @throws IllegalArgumentException if {@code expectedSize} is negative<a name="line.271"></a>
<span class="sourceLineNo">272</span>   * @since 11.0<a name="line.272"></a>
<span class="sourceLineNo">273</span>   */<a name="line.273"></a>
<span class="sourceLineNo">274</span>  public static &lt;E&gt; LinkedHashSet&lt;E&gt; newLinkedHashSetWithExpectedSize(<a name="line.274"></a>
<span class="sourceLineNo">275</span>      int expectedSize) {<a name="line.275"></a>
<span class="sourceLineNo">276</span>    return new LinkedHashSet&lt;E&gt;(Maps.capacity(expectedSize));<a name="line.276"></a>
<span class="sourceLineNo">277</span>  }<a name="line.277"></a>
<span class="sourceLineNo">278</span><a name="line.278"></a>
<span class="sourceLineNo">279</span>  /**<a name="line.279"></a>
<span class="sourceLineNo">280</span>   * Creates a &lt;i&gt;mutable&lt;/i&gt; {@code LinkedHashSet} instance containing the<a name="line.280"></a>
<span class="sourceLineNo">281</span>   * given elements in order.<a name="line.281"></a>
<span class="sourceLineNo">282</span>   *<a name="line.282"></a>
<span class="sourceLineNo">283</span>   * &lt;p&gt;&lt;b&gt;Note:&lt;/b&gt; if mutability is not required and the elements are<a name="line.283"></a>
<span class="sourceLineNo">284</span>   * non-null, use {@link ImmutableSet#copyOf(Iterable)} instead.<a name="line.284"></a>
<span class="sourceLineNo">285</span>   *<a name="line.285"></a>
<span class="sourceLineNo">286</span>   * @param elements the elements that the set should contain, in order<a name="line.286"></a>
<span class="sourceLineNo">287</span>   * @return a new {@code LinkedHashSet} containing those elements (minus<a name="line.287"></a>
<span class="sourceLineNo">288</span>   *     duplicates)<a name="line.288"></a>
<span class="sourceLineNo">289</span>   */<a name="line.289"></a>
<span class="sourceLineNo">290</span>  public static &lt;E&gt; LinkedHashSet&lt;E&gt; newLinkedHashSet(<a name="line.290"></a>
<span class="sourceLineNo">291</span>      Iterable&lt;? extends E&gt; elements) {<a name="line.291"></a>
<span class="sourceLineNo">292</span>    if (elements instanceof Collection) {<a name="line.292"></a>
<span class="sourceLineNo">293</span>      return new LinkedHashSet&lt;E&gt;(Collections2.cast(elements));<a name="line.293"></a>
<span class="sourceLineNo">294</span>    }<a name="line.294"></a>
<span class="sourceLineNo">295</span>    LinkedHashSet&lt;E&gt; set = newLinkedHashSet();<a name="line.295"></a>
<span class="sourceLineNo">296</span>    for (E element : elements) {<a name="line.296"></a>
<span class="sourceLineNo">297</span>      set.add(element);<a name="line.297"></a>
<span class="sourceLineNo">298</span>    }<a name="line.298"></a>
<span class="sourceLineNo">299</span>    return set;<a name="line.299"></a>
<span class="sourceLineNo">300</span>  }<a name="line.300"></a>
<span class="sourceLineNo">301</span><a name="line.301"></a>
<span class="sourceLineNo">302</span>  // TreeSet<a name="line.302"></a>
<span class="sourceLineNo">303</span><a name="line.303"></a>
<span class="sourceLineNo">304</span>  /**<a name="line.304"></a>
<span class="sourceLineNo">305</span>   * Creates a &lt;i&gt;mutable&lt;/i&gt;, empty {@code TreeSet} instance sorted by the<a name="line.305"></a>
<span class="sourceLineNo">306</span>   * natural sort ordering of its elements.<a name="line.306"></a>
<span class="sourceLineNo">307</span>   *<a name="line.307"></a>
<span class="sourceLineNo">308</span>   * &lt;p&gt;&lt;b&gt;Note:&lt;/b&gt; if mutability is not required, use {@link<a name="line.308"></a>
<span class="sourceLineNo">309</span>   * ImmutableSortedSet#of()} instead.<a name="line.309"></a>
<span class="sourceLineNo">310</span>   *<a name="line.310"></a>
<span class="sourceLineNo">311</span>   * @return a new, empty {@code TreeSet}<a name="line.311"></a>
<span class="sourceLineNo">312</span>   */<a name="line.312"></a>
<span class="sourceLineNo">313</span>  public static &lt;E extends Comparable&gt; TreeSet&lt;E&gt; newTreeSet() {<a name="line.313"></a>
<span class="sourceLineNo">314</span>    return new TreeSet&lt;E&gt;();<a name="line.314"></a>
<span class="sourceLineNo">315</span>  }<a name="line.315"></a>
<span class="sourceLineNo">316</span><a name="line.316"></a>
<span class="sourceLineNo">317</span>  /**<a name="line.317"></a>
<span class="sourceLineNo">318</span>   * Creates a &lt;i&gt;mutable&lt;/i&gt; {@code TreeSet} instance containing the given<a name="line.318"></a>
<span class="sourceLineNo">319</span>   * elements sorted by their natural ordering.<a name="line.319"></a>
<span class="sourceLineNo">320</span>   *<a name="line.320"></a>
<span class="sourceLineNo">321</span>   * &lt;p&gt;&lt;b&gt;Note:&lt;/b&gt; if mutability is not required, use {@link<a name="line.321"></a>
<span class="sourceLineNo">322</span>   * ImmutableSortedSet#copyOf(Iterable)} instead.<a name="line.322"></a>
<span class="sourceLineNo">323</span>   *<a name="line.323"></a>
<span class="sourceLineNo">324</span>   * &lt;p&gt;&lt;b&gt;Note:&lt;/b&gt; If {@code elements} is a {@code SortedSet} with an explicit<a name="line.324"></a>
<span class="sourceLineNo">325</span>   * comparator, this method has different behavior than<a name="line.325"></a>
<span class="sourceLineNo">326</span>   * {@link TreeSet#TreeSet(SortedSet)}, which returns a {@code TreeSet} with<a name="line.326"></a>
<span class="sourceLineNo">327</span>   * that comparator.<a name="line.327"></a>
<span class="sourceLineNo">328</span>   *<a name="line.328"></a>
<span class="sourceLineNo">329</span>   * @param elements the elements that the set should contain<a name="line.329"></a>
<span class="sourceLineNo">330</span>   * @return a new {@code TreeSet} containing those elements (minus duplicates)<a name="line.330"></a>
<span class="sourceLineNo">331</span>   */<a name="line.331"></a>
<span class="sourceLineNo">332</span>  public static &lt;E extends Comparable&gt; TreeSet&lt;E&gt; newTreeSet(<a name="line.332"></a>
<span class="sourceLineNo">333</span>      Iterable&lt;? extends E&gt; elements) {<a name="line.333"></a>
<span class="sourceLineNo">334</span>    TreeSet&lt;E&gt; set = newTreeSet();<a name="line.334"></a>
<span class="sourceLineNo">335</span>    for (E element : elements) {<a name="line.335"></a>
<span class="sourceLineNo">336</span>      set.add(element);<a name="line.336"></a>
<span class="sourceLineNo">337</span>    }<a name="line.337"></a>
<span class="sourceLineNo">338</span>    return set;<a name="line.338"></a>
<span class="sourceLineNo">339</span>  }<a name="line.339"></a>
<span class="sourceLineNo">340</span><a name="line.340"></a>
<span class="sourceLineNo">341</span>  /**<a name="line.341"></a>
<span class="sourceLineNo">342</span>   * Creates a &lt;i&gt;mutable&lt;/i&gt;, empty {@code TreeSet} instance with the given<a name="line.342"></a>
<span class="sourceLineNo">343</span>   * comparator.<a name="line.343"></a>
<span class="sourceLineNo">344</span>   *<a name="line.344"></a>
<span class="sourceLineNo">345</span>   * &lt;p&gt;&lt;b&gt;Note:&lt;/b&gt; if mutability is not required, use {@code<a name="line.345"></a>
<span class="sourceLineNo">346</span>   * ImmutableSortedSet.orderedBy(comparator).build()} instead.<a name="line.346"></a>
<span class="sourceLineNo">347</span>   *<a name="line.347"></a>
<span class="sourceLineNo">348</span>   * @param comparator the comparator to use to sort the set<a name="line.348"></a>
<span class="sourceLineNo">349</span>   * @return a new, empty {@code TreeSet}<a name="line.349"></a>
<span class="sourceLineNo">350</span>   * @throws NullPointerException if {@code comparator} is null<a name="line.350"></a>
<span class="sourceLineNo">351</span>   */<a name="line.351"></a>
<span class="sourceLineNo">352</span>  public static &lt;E&gt; TreeSet&lt;E&gt; newTreeSet(Comparator&lt;? super E&gt; comparator) {<a name="line.352"></a>
<span class="sourceLineNo">353</span>    return new TreeSet&lt;E&gt;(checkNotNull(comparator));<a name="line.353"></a>
<span class="sourceLineNo">354</span>  }<a name="line.354"></a>
<span class="sourceLineNo">355</span><a name="line.355"></a>
<span class="sourceLineNo">356</span>  /**<a name="line.356"></a>
<span class="sourceLineNo">357</span>   * Creates an empty {@code Set} that uses identity to determine equality. It<a name="line.357"></a>
<span class="sourceLineNo">358</span>   * compares object references, instead of calling {@code equals}, to<a name="line.358"></a>
<span class="sourceLineNo">359</span>   * determine whether a provided object matches an element in the set. For<a name="line.359"></a>
<span class="sourceLineNo">360</span>   * example, {@code contains} returns {@code false} when passed an object that<a name="line.360"></a>
<span class="sourceLineNo">361</span>   * equals a set member, but isn't the same instance. This behavior is similar<a name="line.361"></a>
<span class="sourceLineNo">362</span>   * to the way {@code IdentityHashMap} handles key lookups.<a name="line.362"></a>
<span class="sourceLineNo">363</span>   *<a name="line.363"></a>
<span class="sourceLineNo">364</span>   * @since 8.0<a name="line.364"></a>
<span class="sourceLineNo">365</span>   */<a name="line.365"></a>
<span class="sourceLineNo">366</span>  public static &lt;E&gt; Set&lt;E&gt; newIdentityHashSet() {<a name="line.366"></a>
<span class="sourceLineNo">367</span>    return Sets.newSetFromMap(Maps.&lt;E, Boolean&gt;newIdentityHashMap());<a name="line.367"></a>
<span class="sourceLineNo">368</span>  }<a name="line.368"></a>
<span class="sourceLineNo">369</span><a name="line.369"></a>
<span class="sourceLineNo">370</span>  /**<a name="line.370"></a>
<span class="sourceLineNo">371</span>   * Creates an empty {@code CopyOnWriteArraySet} instance.<a name="line.371"></a>
<span class="sourceLineNo">372</span>   *<a name="line.372"></a>
<span class="sourceLineNo">373</span>   * &lt;p&gt;&lt;b&gt;Note:&lt;/b&gt; if you need an immutable empty {@link Set}, use<a name="line.373"></a>
<span class="sourceLineNo">374</span>   * {@link Collections#emptySet} instead.<a name="line.374"></a>
<span class="sourceLineNo">375</span>   *<a name="line.375"></a>
<span class="sourceLineNo">376</span>   * @return a new, empty {@code CopyOnWriteArraySet}<a name="line.376"></a>
<span class="sourceLineNo">377</span>   * @since 12.0<a name="line.377"></a>
<span class="sourceLineNo">378</span>   */<a name="line.378"></a>
<span class="sourceLineNo">379</span>  @GwtIncompatible("CopyOnWriteArraySet")<a name="line.379"></a>
<span class="sourceLineNo">380</span>  public static &lt;E&gt; CopyOnWriteArraySet&lt;E&gt; newCopyOnWriteArraySet() {<a name="line.380"></a>
<span class="sourceLineNo">381</span>    return new CopyOnWriteArraySet&lt;E&gt;();<a name="line.381"></a>
<span class="sourceLineNo">382</span>  }<a name="line.382"></a>
<span class="sourceLineNo">383</span><a name="line.383"></a>
<span class="sourceLineNo">384</span>  /**<a name="line.384"></a>
<span class="sourceLineNo">385</span>   * Creates a {@code CopyOnWriteArraySet} instance containing the given elements.<a name="line.385"></a>
<span class="sourceLineNo">386</span>   *<a name="line.386"></a>
<span class="sourceLineNo">387</span>   * @param elements the elements that the set should contain, in order<a name="line.387"></a>
<span class="sourceLineNo">388</span>   * @return a new {@code CopyOnWriteArraySet} containing those elements<a name="line.388"></a>
<span class="sourceLineNo">389</span>   * @since 12.0<a name="line.389"></a>
<span class="sourceLineNo">390</span>   */<a name="line.390"></a>
<span class="sourceLineNo">391</span>  @GwtIncompatible("CopyOnWriteArraySet")<a name="line.391"></a>
<span class="sourceLineNo">392</span>  public static &lt;E&gt; CopyOnWriteArraySet&lt;E&gt; newCopyOnWriteArraySet(<a name="line.392"></a>
<span class="sourceLineNo">393</span>      Iterable&lt;? extends E&gt; elements) {<a name="line.393"></a>
<span class="sourceLineNo">394</span>    // We copy elements to an ArrayList first, rather than incurring the<a name="line.394"></a>
<span class="sourceLineNo">395</span>    // quadratic cost of adding them to the COWAS directly.<a name="line.395"></a>
<span class="sourceLineNo">396</span>    Collection&lt;? extends E&gt; elementsCollection = (elements instanceof Collection)<a name="line.396"></a>
<span class="sourceLineNo">397</span>        ? Collections2.cast(elements)<a name="line.397"></a>
<span class="sourceLineNo">398</span>        : Lists.newArrayList(elements);<a name="line.398"></a>
<span class="sourceLineNo">399</span>    return new CopyOnWriteArraySet&lt;E&gt;(elementsCollection);<a name="line.399"></a>
<span class="sourceLineNo">400</span>  }<a name="line.400"></a>
<span class="sourceLineNo">401</span><a name="line.401"></a>
<span class="sourceLineNo">402</span>  /**<a name="line.402"></a>
<span class="sourceLineNo">403</span>   * Creates an {@code EnumSet} consisting of all enum values that are not in<a name="line.403"></a>
<span class="sourceLineNo">404</span>   * the specified collection. If the collection is an {@link EnumSet}, this<a name="line.404"></a>
<span class="sourceLineNo">405</span>   * method has the same behavior as {@link EnumSet#complementOf}. Otherwise,<a name="line.405"></a>
<span class="sourceLineNo">406</span>   * the specified collection must contain at least one element, in order to<a name="line.406"></a>
<span class="sourceLineNo">407</span>   * determine the element type. If the collection could be empty, use<a name="line.407"></a>
<span class="sourceLineNo">408</span>   * {@link #complementOf(Collection, Class)} instead of this method.<a name="line.408"></a>
<span class="sourceLineNo">409</span>   *<a name="line.409"></a>
<span class="sourceLineNo">410</span>   * @param collection the collection whose complement should be stored in the<a name="line.410"></a>
<span class="sourceLineNo">411</span>   *     enum set<a name="line.411"></a>
<span class="sourceLineNo">412</span>   * @return a new, modifiable {@code EnumSet} containing all values of the enum<a name="line.412"></a>
<span class="sourceLineNo">413</span>   *     that aren't present in the given collection<a name="line.413"></a>
<span class="sourceLineNo">414</span>   * @throws IllegalArgumentException if {@code collection} is not an<a name="line.414"></a>
<span class="sourceLineNo">415</span>   *     {@code EnumSet} instance and contains no elements<a name="line.415"></a>
<span class="sourceLineNo">416</span>   */<a name="line.416"></a>
<span class="sourceLineNo">417</span>  public static &lt;E extends Enum&lt;E&gt;&gt; EnumSet&lt;E&gt; complementOf(<a name="line.417"></a>
<span class="sourceLineNo">418</span>      Collection&lt;E&gt; collection) {<a name="line.418"></a>
<span class="sourceLineNo">419</span>    if (collection instanceof EnumSet) {<a name="line.419"></a>
<span class="sourceLineNo">420</span>      return EnumSet.complementOf((EnumSet&lt;E&gt;) collection);<a name="line.420"></a>
<span class="sourceLineNo">421</span>    }<a name="line.421"></a>
<span class="sourceLineNo">422</span>    checkArgument(!collection.isEmpty(),<a name="line.422"></a>
<span class="sourceLineNo">423</span>        "collection is empty; use the other version of this method");<a name="line.423"></a>
<span class="sourceLineNo">424</span>    Class&lt;E&gt; type = collection.iterator().next().getDeclaringClass();<a name="line.424"></a>
<span class="sourceLineNo">425</span>    return makeComplementByHand(collection, type);<a name="line.425"></a>
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<span class="sourceLineNo">427</span><a name="line.427"></a>
<span class="sourceLineNo">428</span>  /**<a name="line.428"></a>
<span class="sourceLineNo">429</span>   * Creates an {@code EnumSet} consisting of all enum values that are not in<a name="line.429"></a>
<span class="sourceLineNo">430</span>   * the specified collection. This is equivalent to<a name="line.430"></a>
<span class="sourceLineNo">431</span>   * {@link EnumSet#complementOf}, but can act on any input collection, as long<a name="line.431"></a>
<span class="sourceLineNo">432</span>   * as the elements are of enum type.<a name="line.432"></a>
<span class="sourceLineNo">433</span>   *<a name="line.433"></a>
<span class="sourceLineNo">434</span>   * @param collection the collection whose complement should be stored in the<a name="line.434"></a>
<span class="sourceLineNo">435</span>   *     {@code EnumSet}<a name="line.435"></a>
<span class="sourceLineNo">436</span>   * @param type the type of the elements in the set<a name="line.436"></a>
<span class="sourceLineNo">437</span>   * @return a new, modifiable {@code EnumSet} initially containing all the<a name="line.437"></a>
<span class="sourceLineNo">438</span>   *     values of the enum not present in the given collection<a name="line.438"></a>
<span class="sourceLineNo">439</span>   */<a name="line.439"></a>
<span class="sourceLineNo">440</span>  public static &lt;E extends Enum&lt;E&gt;&gt; EnumSet&lt;E&gt; complementOf(<a name="line.440"></a>
<span class="sourceLineNo">441</span>      Collection&lt;E&gt; collection, Class&lt;E&gt; type) {<a name="line.441"></a>
<span class="sourceLineNo">442</span>    checkNotNull(collection);<a name="line.442"></a>
<span class="sourceLineNo">443</span>    return (collection instanceof EnumSet)<a name="line.443"></a>
<span class="sourceLineNo">444</span>        ? EnumSet.complementOf((EnumSet&lt;E&gt;) collection)<a name="line.444"></a>
<span class="sourceLineNo">445</span>        : makeComplementByHand(collection, type);<a name="line.445"></a>
<span class="sourceLineNo">446</span>  }<a name="line.446"></a>
<span class="sourceLineNo">447</span><a name="line.447"></a>
<span class="sourceLineNo">448</span>  private static &lt;E extends Enum&lt;E&gt;&gt; EnumSet&lt;E&gt; makeComplementByHand(<a name="line.448"></a>
<span class="sourceLineNo">449</span>      Collection&lt;E&gt; collection, Class&lt;E&gt; type) {<a name="line.449"></a>
<span class="sourceLineNo">450</span>    EnumSet&lt;E&gt; result = EnumSet.allOf(type);<a name="line.450"></a>
<span class="sourceLineNo">451</span>    result.removeAll(collection);<a name="line.451"></a>
<span class="sourceLineNo">452</span>    return result;<a name="line.452"></a>
<span class="sourceLineNo">453</span>  }<a name="line.453"></a>
<span class="sourceLineNo">454</span><a name="line.454"></a>
<span class="sourceLineNo">455</span>  /*<a name="line.455"></a>
<span class="sourceLineNo">456</span>   * Regarding newSetForMap() and SetFromMap:<a name="line.456"></a>
<span class="sourceLineNo">457</span>   *<a name="line.457"></a>
<span class="sourceLineNo">458</span>   * Written by Doug Lea with assistance from members of JCP JSR-166<a name="line.458"></a>
<span class="sourceLineNo">459</span>   * Expert Group and released to the public domain, as explained at<a name="line.459"></a>
<span class="sourceLineNo">460</span>   * http://creativecommons.org/licenses/publicdomain<a name="line.460"></a>
<span class="sourceLineNo">461</span>   */<a name="line.461"></a>
<span class="sourceLineNo">462</span><a name="line.462"></a>
<span class="sourceLineNo">463</span>  /**<a name="line.463"></a>
<span class="sourceLineNo">464</span>   * Returns a set backed by the specified map. The resulting set displays<a name="line.464"></a>
<span class="sourceLineNo">465</span>   * the same ordering, concurrency, and performance characteristics as the<a name="line.465"></a>
<span class="sourceLineNo">466</span>   * backing map. In essence, this factory method provides a {@link Set}<a name="line.466"></a>
<span class="sourceLineNo">467</span>   * implementation corresponding to any {@link Map} implementation. There is no<a name="line.467"></a>
<span class="sourceLineNo">468</span>   * need to use this method on a {@link Map} implementation that already has a<a name="line.468"></a>
<span class="sourceLineNo">469</span>   * corresponding {@link Set} implementation (such as {@link java.util.HashMap}<a name="line.469"></a>
<span class="sourceLineNo">470</span>   * or {@link java.util.TreeMap}).<a name="line.470"></a>
<span class="sourceLineNo">471</span>   *<a name="line.471"></a>
<span class="sourceLineNo">472</span>   * &lt;p&gt;Each method invocation on the set returned by this method results in<a name="line.472"></a>
<span class="sourceLineNo">473</span>   * exactly one method invocation on the backing map or its {@code keySet}<a name="line.473"></a>
<span class="sourceLineNo">474</span>   * view, with one exception. The {@code addAll} method is implemented as a<a name="line.474"></a>
<span class="sourceLineNo">475</span>   * sequence of {@code put} invocations on the backing map.<a name="line.475"></a>
<span class="sourceLineNo">476</span>   *<a name="line.476"></a>
<span class="sourceLineNo">477</span>   * &lt;p&gt;The specified map must be empty at the time this method is invoked,<a name="line.477"></a>
<span class="sourceLineNo">478</span>   * and should not be accessed directly after this method returns. These<a name="line.478"></a>
<span class="sourceLineNo">479</span>   * conditions are ensured if the map is created empty, passed directly<a name="line.479"></a>
<span class="sourceLineNo">480</span>   * to this method, and no reference to the map is retained, as illustrated<a name="line.480"></a>
<span class="sourceLineNo">481</span>   * in the following code fragment: &lt;pre&gt;  {@code<a name="line.481"></a>
<span class="sourceLineNo">482</span>   *<a name="line.482"></a>
<span class="sourceLineNo">483</span>   *   Set&lt;Object&gt; identityHashSet = Sets.newSetFromMap(<a name="line.483"></a>
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<span class="sourceLineNo">485</span>   *<a name="line.485"></a>
<span class="sourceLineNo">486</span>   * This method has the same behavior as the JDK 6 method<a name="line.486"></a>
<span class="sourceLineNo">487</span>   * {@code Collections.newSetFromMap()}. The returned set is serializable if<a name="line.487"></a>
<span class="sourceLineNo">488</span>   * the backing map is.<a name="line.488"></a>
<span class="sourceLineNo">489</span>   *<a name="line.489"></a>
<span class="sourceLineNo">490</span>   * @param map the backing map<a name="line.490"></a>
<span class="sourceLineNo">491</span>   * @return the set backed by the map<a name="line.491"></a>
<span class="sourceLineNo">492</span>   * @throws IllegalArgumentException if {@code map} is not empty<a name="line.492"></a>
<span class="sourceLineNo">493</span>   */<a name="line.493"></a>
<span class="sourceLineNo">494</span>  public static &lt;E&gt; Set&lt;E&gt; newSetFromMap(Map&lt;E, Boolean&gt; map) {<a name="line.494"></a>
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<span class="sourceLineNo">498</span>  private static class SetFromMap&lt;E&gt; extends AbstractSet&lt;E&gt;<a name="line.498"></a>
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<span class="sourceLineNo">500</span>    private final Map&lt;E, Boolean&gt; m; // The backing map<a name="line.500"></a>
<span class="sourceLineNo">501</span>    private transient Set&lt;E&gt; s; // Its keySet<a name="line.501"></a>
<span class="sourceLineNo">502</span><a name="line.502"></a>
<span class="sourceLineNo">503</span>    SetFromMap(Map&lt;E, Boolean&gt; map) {<a name="line.503"></a>
<span class="sourceLineNo">504</span>      checkArgument(map.isEmpty(), "Map is non-empty");<a name="line.504"></a>
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<span class="sourceLineNo">508</span><a name="line.508"></a>
<span class="sourceLineNo">509</span>    @Override public void clear() {<a name="line.509"></a>
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<span class="sourceLineNo">512</span>    @Override public int size() {<a name="line.512"></a>
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<span class="sourceLineNo">515</span>    @Override public boolean isEmpty() {<a name="line.515"></a>
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<span class="sourceLineNo">524</span>    @Override public boolean add(E e) {<a name="line.524"></a>
<span class="sourceLineNo">525</span>      return m.put(e, Boolean.TRUE) == null;<a name="line.525"></a>
<span class="sourceLineNo">526</span>    }<a name="line.526"></a>
<span class="sourceLineNo">527</span>    @Override public Iterator&lt;E&gt; iterator() {<a name="line.527"></a>
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<span class="sourceLineNo">530</span>    @Override public Object[] toArray() {<a name="line.530"></a>
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<span class="sourceLineNo">539</span>    @Override public int hashCode() {<a name="line.539"></a>
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<span class="sourceLineNo">551</span>    @Override public boolean retainAll(Collection&lt;?&gt; c) {<a name="line.551"></a>
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<span class="sourceLineNo">554</span><a name="line.554"></a>
<span class="sourceLineNo">555</span>    // addAll is the only inherited implementation<a name="line.555"></a>
<span class="sourceLineNo">556</span>    @GwtIncompatible("not needed in emulated source")<a name="line.556"></a>
<span class="sourceLineNo">557</span>    private static final long serialVersionUID = 0;<a name="line.557"></a>
<span class="sourceLineNo">558</span><a name="line.558"></a>
<span class="sourceLineNo">559</span>    @GwtIncompatible("java.io.ObjectInputStream")<a name="line.559"></a>
<span class="sourceLineNo">560</span>    private void readObject(ObjectInputStream stream)<a name="line.560"></a>
<span class="sourceLineNo">561</span>        throws IOException, ClassNotFoundException {<a name="line.561"></a>
<span class="sourceLineNo">562</span>      stream.defaultReadObject();<a name="line.562"></a>
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<span class="sourceLineNo">567</span>  /**<a name="line.567"></a>
<span class="sourceLineNo">568</span>   * An unmodifiable view of a set which may be backed by other sets; this view<a name="line.568"></a>
<span class="sourceLineNo">569</span>   * will change as the backing sets do. Contains methods to copy the data into<a name="line.569"></a>
<span class="sourceLineNo">570</span>   * a new set which will then remain stable. There is usually no reason to<a name="line.570"></a>
<span class="sourceLineNo">571</span>   * retain a reference of type {@code SetView}; typically, you either use it<a name="line.571"></a>
<span class="sourceLineNo">572</span>   * as a plain {@link Set}, or immediately invoke {@link #immutableCopy} or<a name="line.572"></a>
<span class="sourceLineNo">573</span>   * {@link #copyInto} and forget the {@code SetView} itself.<a name="line.573"></a>
<span class="sourceLineNo">574</span>   *<a name="line.574"></a>
<span class="sourceLineNo">575</span>   * @since 2.0 (imported from Google Collections Library)<a name="line.575"></a>
<span class="sourceLineNo">576</span>   */<a name="line.576"></a>
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<span class="sourceLineNo">578</span>    private SetView() {} // no subclasses but our own<a name="line.578"></a>
<span class="sourceLineNo">579</span><a name="line.579"></a>
<span class="sourceLineNo">580</span>    /**<a name="line.580"></a>
<span class="sourceLineNo">581</span>     * Returns an immutable copy of the current contents of this set view.<a name="line.581"></a>
<span class="sourceLineNo">582</span>     * Does not support null elements.<a name="line.582"></a>
<span class="sourceLineNo">583</span>     *<a name="line.583"></a>
<span class="sourceLineNo">584</span>     * &lt;p&gt;&lt;b&gt;Warning:&lt;/b&gt; this may have unexpected results if a backing set of<a name="line.584"></a>
<span class="sourceLineNo">585</span>     * this view uses a nonstandard notion of equivalence, for example if it is<a name="line.585"></a>
<span class="sourceLineNo">586</span>     * a {@link TreeSet} using a comparator that is inconsistent with {@link<a name="line.586"></a>
<span class="sourceLineNo">587</span>     * Object#equals(Object)}.<a name="line.587"></a>
<span class="sourceLineNo">588</span>     */<a name="line.588"></a>
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<span class="sourceLineNo">592</span><a name="line.592"></a>
<span class="sourceLineNo">593</span>    /**<a name="line.593"></a>
<span class="sourceLineNo">594</span>     * Copies the current contents of this set view into an existing set. This<a name="line.594"></a>
<span class="sourceLineNo">595</span>     * method has equivalent behavior to {@code set.addAll(this)}, assuming that<a name="line.595"></a>
<span class="sourceLineNo">596</span>     * all the sets involved are based on the same notion of equivalence.<a name="line.596"></a>
<span class="sourceLineNo">597</span>     *<a name="line.597"></a>
<span class="sourceLineNo">598</span>     * @return a reference to {@code set}, for convenience<a name="line.598"></a>
<span class="sourceLineNo">599</span>     */<a name="line.599"></a>
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<span class="sourceLineNo">601</span>    // some javac bug or some weirdness in the spec, not sure which.<a name="line.601"></a>
<span class="sourceLineNo">602</span>    public &lt;S extends Set&lt;E&gt;&gt; S copyInto(S set) {<a name="line.602"></a>
<span class="sourceLineNo">603</span>      set.addAll(this);<a name="line.603"></a>
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<span class="sourceLineNo">608</span>  /**<a name="line.608"></a>
<span class="sourceLineNo">609</span>   * Returns an unmodifiable &lt;b&gt;view&lt;/b&gt; of the union of two sets. The returned<a name="line.609"></a>
<span class="sourceLineNo">610</span>   * set contains all elements that are contained in either backing set.<a name="line.610"></a>
<span class="sourceLineNo">611</span>   * Iterating over the returned set iterates first over all the elements of<a name="line.611"></a>
<span class="sourceLineNo">612</span>   * {@code set1}, then over each element of {@code set2}, in order, that is not<a name="line.612"></a>
<span class="sourceLineNo">613</span>   * contained in {@code set1}.<a name="line.613"></a>
<span class="sourceLineNo">614</span>   *<a name="line.614"></a>
<span class="sourceLineNo">615</span>   * &lt;p&gt;Results are undefined if {@code set1} and {@code set2} are sets based on<a name="line.615"></a>
<span class="sourceLineNo">616</span>   * different equivalence relations (as {@link HashSet}, {@link TreeSet}, and<a name="line.616"></a>
<span class="sourceLineNo">617</span>   * the {@link Map#keySet} of an {@code IdentityHashMap} all are).<a name="line.617"></a>
<span class="sourceLineNo">618</span>   *<a name="line.618"></a>
<span class="sourceLineNo">619</span>   * &lt;p&gt;&lt;b&gt;Note:&lt;/b&gt; The returned view performs better when {@code set1} is the<a name="line.619"></a>
<span class="sourceLineNo">620</span>   * smaller of the two sets. If you have reason to believe one of your sets<a name="line.620"></a>
<span class="sourceLineNo">621</span>   * will generally be smaller than the other, pass it first.<a name="line.621"></a>
<span class="sourceLineNo">622</span>   *<a name="line.622"></a>
<span class="sourceLineNo">623</span>   * &lt;p&gt;Further, note that the current implementation is not suitable for nested<a name="line.623"></a>
<span class="sourceLineNo">624</span>   * {@code union} views, i.e. the following should be avoided when in a loop:<a name="line.624"></a>
<span class="sourceLineNo">625</span>   * {@code union = Sets.union(union, anotherSet);}, since iterating over the resulting<a name="line.625"></a>
<span class="sourceLineNo">626</span>   * set has a cubic complexity to the depth of the nesting.<a name="line.626"></a>
<span class="sourceLineNo">627</span>   */<a name="line.627"></a>
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<span class="sourceLineNo">637</span>        return set1.size() + set2minus1.size();<a name="line.637"></a>
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<span class="sourceLineNo">639</span>      @Override public boolean isEmpty() {<a name="line.639"></a>
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<span class="sourceLineNo">642</span>      @Override public Iterator&lt;E&gt; iterator() {<a name="line.642"></a>
<span class="sourceLineNo">643</span>        return Iterators.unmodifiableIterator(<a name="line.643"></a>
<span class="sourceLineNo">644</span>            Iterators.concat(set1.iterator(), set2minus1.iterator()));<a name="line.644"></a>
<span class="sourceLineNo">645</span>      }<a name="line.645"></a>
<span class="sourceLineNo">646</span>      @Override public boolean contains(Object object) {<a name="line.646"></a>
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<span class="sourceLineNo">649</span>      @Override public &lt;S extends Set&lt;E&gt;&gt; S copyInto(S set) {<a name="line.649"></a>
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<span class="sourceLineNo">651</span>        set.addAll(set2);<a name="line.651"></a>
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<span class="sourceLineNo">655</span>        return new ImmutableSet.Builder&lt;E&gt;()<a name="line.655"></a>
<span class="sourceLineNo">656</span>            .addAll(set1).addAll(set2).build();<a name="line.656"></a>
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<span class="sourceLineNo">661</span>  /**<a name="line.661"></a>
<span class="sourceLineNo">662</span>   * Returns an unmodifiable &lt;b&gt;view&lt;/b&gt; of the intersection of two sets. The<a name="line.662"></a>
<span class="sourceLineNo">663</span>   * returned set contains all elements that are contained by both backing sets.<a name="line.663"></a>
<span class="sourceLineNo">664</span>   * The iteration order of the returned set matches that of {@code set1}.<a name="line.664"></a>
<span class="sourceLineNo">665</span>   *<a name="line.665"></a>
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<span class="sourceLineNo">667</span>   * on different equivalence relations (as {@code HashSet}, {@code TreeSet},<a name="line.667"></a>
<span class="sourceLineNo">668</span>   * and the keySet of an {@code IdentityHashMap} all are).<a name="line.668"></a>
<span class="sourceLineNo">669</span>   *<a name="line.669"></a>
<span class="sourceLineNo">670</span>   * &lt;p&gt;&lt;b&gt;Note:&lt;/b&gt; The returned view performs slightly better when {@code<a name="line.670"></a>
<span class="sourceLineNo">671</span>   * set1} is the smaller of the two sets. If you have reason to believe one of<a name="line.671"></a>
<span class="sourceLineNo">672</span>   * your sets will generally be smaller than the other, pass it first.<a name="line.672"></a>
<span class="sourceLineNo">673</span>   * Unfortunately, since this method sets the generic type of the returned set<a name="line.673"></a>
<span class="sourceLineNo">674</span>   * based on the type of the first set passed, this could in rare cases force<a name="line.674"></a>
<span class="sourceLineNo">675</span>   * you to make a cast, for example: &lt;pre&gt;   {@code<a name="line.675"></a>
<span class="sourceLineNo">676</span>   *<a name="line.676"></a>
<span class="sourceLineNo">677</span>   *   Set&lt;Object&gt; aFewBadObjects = ...<a name="line.677"></a>
<span class="sourceLineNo">678</span>   *   Set&lt;String&gt; manyBadStrings = ...<a name="line.678"></a>
<span class="sourceLineNo">679</span>   *<a name="line.679"></a>
<span class="sourceLineNo">680</span>   *   // impossible for a non-String to be in the intersection<a name="line.680"></a>
<span class="sourceLineNo">681</span>   *   SuppressWarnings("unchecked")<a name="line.681"></a>
<span class="sourceLineNo">682</span>   *   Set&lt;String&gt; badStrings = (Set) Sets.intersection(<a name="line.682"></a>
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<span class="sourceLineNo">684</span>   *<a name="line.684"></a>
<span class="sourceLineNo">685</span>   * This is unfortunate, but should come up only very rarely.<a name="line.685"></a>
<span class="sourceLineNo">686</span>   */<a name="line.686"></a>
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<span class="sourceLineNo">717</span>   * present in {@code set1}; these are simply ignored. The iteration order of<a name="line.717"></a>
<span class="sourceLineNo">718</span>   * the returned set matches that of {@code set1}.<a name="line.718"></a>
<span class="sourceLineNo">719</span>   *<a name="line.719"></a>
<span class="sourceLineNo">720</span>   * &lt;p&gt;Results are undefined if {@code set1} and {@code set2} are sets based<a name="line.720"></a>
<span class="sourceLineNo">721</span>   * on different equivalence relations (as {@code HashSet}, {@code TreeSet},<a name="line.721"></a>
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<span class="sourceLineNo">750</span>   * returned set is undefined.<a name="line.750"></a>
<span class="sourceLineNo">751</span>   *<a name="line.751"></a>
<span class="sourceLineNo">752</span>   * &lt;p&gt;Results are undefined if {@code set1} and {@code set2} are sets based<a name="line.752"></a>
<span class="sourceLineNo">753</span>   * on different equivalence relations (as {@code HashSet}, {@code TreeSet},<a name="line.753"></a>
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<span class="sourceLineNo">755</span>   *<a name="line.755"></a>
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<span class="sourceLineNo">771</span>   *<a name="line.771"></a>
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<span class="sourceLineNo">781</span>   *<a name="line.781"></a>
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<span class="sourceLineNo">783</span>   * across every element in the underlying set and determine which elements<a name="line.783"></a>
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<span class="sourceLineNo">831</span>   * changes to one affect the other.<a name="line.831"></a>
<span class="sourceLineNo">832</span>   *<a name="line.832"></a>
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<span class="sourceLineNo">834</span>   * other set methods are supported. When given an element that doesn't satisfy<a name="line.834"></a>
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<span class="sourceLineNo">840</span>   *<a name="line.840"></a>
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<span class="sourceLineNo">842</span>   * {@code unfiltered} is.<a name="line.842"></a>
<span class="sourceLineNo">843</span>   *<a name="line.843"></a>
<span class="sourceLineNo">844</span>   * &lt;p&gt;Many of the filtered set's methods, such as {@code size()}, iterate across<a name="line.844"></a>
<span class="sourceLineNo">845</span>   * every element in the underlying set and determine which elements satisfy<a name="line.845"></a>
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<span class="sourceLineNo">847</span>   * {@code Iterables.filter(unfiltered, predicate)} and use the copy.<a name="line.847"></a>
<span class="sourceLineNo">848</span>   *<a name="line.848"></a>
<span class="sourceLineNo">849</span>   * &lt;p&gt;&lt;b&gt;Warning:&lt;/b&gt; {@code predicate} must be &lt;i&gt;consistent with equals&lt;/i&gt;,<a name="line.849"></a>
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<span class="sourceLineNo">851</span>   * {@code Predicates.instanceOf(ArrayList.class)}, which is inconsistent with<a name="line.851"></a>
<span class="sourceLineNo">852</span>   * equals. (See {@link Iterables#filter(Iterable, Class)} for related<a name="line.852"></a>
<span class="sourceLineNo">853</span>   * functionality.)<a name="line.853"></a>
<span class="sourceLineNo">854</span>   *<a name="line.854"></a>
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<span class="sourceLineNo">862</span>  static &lt;E&gt; SortedSet&lt;E&gt; filterSortedIgnoreNavigable(<a name="line.862"></a>
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<span class="sourceLineNo">890</span>    @Override<a name="line.890"></a>
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<span class="sourceLineNo">906</span>    @Override<a name="line.906"></a>
<span class="sourceLineNo">907</span>    public E first() {<a name="line.907"></a>
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<span class="sourceLineNo">928</span>   *<a name="line.928"></a>
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<span class="sourceLineNo">930</span>   * other set methods are supported. When given an element that doesn't satisfy<a name="line.930"></a>
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<span class="sourceLineNo">936</span>   *<a name="line.936"></a>
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<span class="sourceLineNo">939</span>   *<a name="line.939"></a>
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<span class="sourceLineNo">941</span>   * every element in the underlying set and determine which elements satisfy<a name="line.941"></a>
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<span class="sourceLineNo">944</span>   *<a name="line.944"></a>
<span class="sourceLineNo">945</span>   * &lt;p&gt;&lt;b&gt;Warning:&lt;/b&gt; {@code predicate} must be &lt;i&gt;consistent with equals&lt;/i&gt;,<a name="line.945"></a>
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<span class="sourceLineNo">947</span>   * {@code Predicates.instanceOf(ArrayList.class)}, which is inconsistent with<a name="line.947"></a>
<span class="sourceLineNo">948</span>   * equals. (See {@link Iterables#filter(Iterable, Class)} for related<a name="line.948"></a>
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<span class="sourceLineNo">950</span>   *<a name="line.950"></a>
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<span class="sourceLineNo">954</span>  @SuppressWarnings("unchecked")<a name="line.954"></a>
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<span class="sourceLineNo">1063</span>  /**<a name="line.1063"></a>
<span class="sourceLineNo">1064</span>   * Returns every possible list that can be formed by choosing one element<a name="line.1064"></a>
<span class="sourceLineNo">1065</span>   * from each of the given sets in order; the "n-ary<a name="line.1065"></a>
<span class="sourceLineNo">1066</span>   * &lt;a href="http://en.wikipedia.org/wiki/Cartesian_product"&gt;Cartesian<a name="line.1066"></a>
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<span class="sourceLineNo">1068</span>   *<a name="line.1068"></a>
<span class="sourceLineNo">1069</span>   *   Sets.cartesianProduct(ImmutableList.of(<a name="line.1069"></a>
<span class="sourceLineNo">1070</span>   *       ImmutableSet.of(1, 2),<a name="line.1070"></a>
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<span class="sourceLineNo">1072</span>   *<a name="line.1072"></a>
<span class="sourceLineNo">1073</span>   * returns a set containing six lists:<a name="line.1073"></a>
<span class="sourceLineNo">1074</span>   *<a name="line.1074"></a>
<span class="sourceLineNo">1075</span>   * &lt;ul&gt;<a name="line.1075"></a>
<span class="sourceLineNo">1076</span>   * &lt;li&gt;{@code ImmutableList.of(1, "A")}<a name="line.1076"></a>
<span class="sourceLineNo">1077</span>   * &lt;li&gt;{@code ImmutableList.of(1, "B")}<a name="line.1077"></a>
<span class="sourceLineNo">1078</span>   * &lt;li&gt;{@code ImmutableList.of(1, "C")}<a name="line.1078"></a>
<span class="sourceLineNo">1079</span>   * &lt;li&gt;{@code ImmutableList.of(2, "A")}<a name="line.1079"></a>
<span class="sourceLineNo">1080</span>   * &lt;li&gt;{@code ImmutableList.of(2, "B")}<a name="line.1080"></a>
<span class="sourceLineNo">1081</span>   * &lt;li&gt;{@code ImmutableList.of(2, "C")}<a name="line.1081"></a>
<span class="sourceLineNo">1082</span>   * &lt;/ul&gt;<a name="line.1082"></a>
<span class="sourceLineNo">1083</span>   *<a name="line.1083"></a>
<span class="sourceLineNo">1084</span>   * The result is guaranteed to be in the "traditional", lexicographical<a name="line.1084"></a>
<span class="sourceLineNo">1085</span>   * order for Cartesian products that you would get from nesting for loops:<a name="line.1085"></a>
<span class="sourceLineNo">1086</span>   * &lt;pre&gt;   {@code<a name="line.1086"></a>
<span class="sourceLineNo">1087</span>   *<a name="line.1087"></a>
<span class="sourceLineNo">1088</span>   *   for (B b0 : sets.get(0)) {<a name="line.1088"></a>
<span class="sourceLineNo">1089</span>   *     for (B b1 : sets.get(1)) {<a name="line.1089"></a>
<span class="sourceLineNo">1090</span>   *       ...<a name="line.1090"></a>
<span class="sourceLineNo">1091</span>   *       ImmutableList&lt;B&gt; tuple = ImmutableList.of(b0, b1, ...);<a name="line.1091"></a>
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<span class="sourceLineNo">1095</span>   *<a name="line.1095"></a>
<span class="sourceLineNo">1096</span>   * Note that if any input set is empty, the Cartesian product will also be<a name="line.1096"></a>
<span class="sourceLineNo">1097</span>   * empty. If no sets at all are provided (an empty list), the resulting<a name="line.1097"></a>
<span class="sourceLineNo">1098</span>   * Cartesian product has one element, an empty list (counter-intuitive, but<a name="line.1098"></a>
<span class="sourceLineNo">1099</span>   * mathematically consistent).<a name="line.1099"></a>
<span class="sourceLineNo">1100</span>   *<a name="line.1100"></a>
<span class="sourceLineNo">1101</span>   * &lt;p&gt;&lt;i&gt;Performance notes:&lt;/i&gt; while the cartesian product of sets of size<a name="line.1101"></a>
<span class="sourceLineNo">1102</span>   * {@code m, n, p} is a set of size {@code m x n x p}, its actual memory<a name="line.1102"></a>
<span class="sourceLineNo">1103</span>   * consumption is much smaller. When the cartesian set is constructed, the<a name="line.1103"></a>
<span class="sourceLineNo">1104</span>   * input sets are merely copied. Only as the resulting set is iterated are the<a name="line.1104"></a>
<span class="sourceLineNo">1105</span>   * individual lists created, and these are not retained after iteration.<a name="line.1105"></a>
<span class="sourceLineNo">1106</span>   *<a name="line.1106"></a>
<span class="sourceLineNo">1107</span>   * @param sets the sets to choose elements from, in the order that<a name="line.1107"></a>
<span class="sourceLineNo">1108</span>   *     the elements chosen from those sets should appear in the resulting<a name="line.1108"></a>
<span class="sourceLineNo">1109</span>   *     lists<a name="line.1109"></a>
<span class="sourceLineNo">1110</span>   * @param &lt;B&gt; any common base class shared by all axes (often just {@link<a name="line.1110"></a>
<span class="sourceLineNo">1111</span>   *     Object})<a name="line.1111"></a>
<span class="sourceLineNo">1112</span>   * @return the Cartesian product, as an immutable set containing immutable<a name="line.1112"></a>
<span class="sourceLineNo">1113</span>   *     lists<a name="line.1113"></a>
<span class="sourceLineNo">1114</span>   * @throws NullPointerException if {@code sets}, any one of the {@code sets},<a name="line.1114"></a>
<span class="sourceLineNo">1115</span>   *     or any element of a provided set is null<a name="line.1115"></a>
<span class="sourceLineNo">1116</span>   * @since 2.0<a name="line.1116"></a>
<span class="sourceLineNo">1117</span>   */<a name="line.1117"></a>
<span class="sourceLineNo">1118</span>  public static &lt;B&gt; Set&lt;List&lt;B&gt;&gt; cartesianProduct(<a name="line.1118"></a>
<span class="sourceLineNo">1119</span>      List&lt;? extends Set&lt;? extends B&gt;&gt; sets) {<a name="line.1119"></a>
<span class="sourceLineNo">1120</span>    for (Set&lt;? extends B&gt; set : sets) {<a name="line.1120"></a>
<span class="sourceLineNo">1121</span>      if (set.isEmpty()) {<a name="line.1121"></a>
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<span class="sourceLineNo">1125</span>    return CartesianSet.create(sets);<a name="line.1125"></a>
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<span class="sourceLineNo">1127</span><a name="line.1127"></a>
<span class="sourceLineNo">1128</span>  /**<a name="line.1128"></a>
<span class="sourceLineNo">1129</span>   * Returns every possible list that can be formed by choosing one element<a name="line.1129"></a>
<span class="sourceLineNo">1130</span>   * from each of the given sets in order; the "n-ary<a name="line.1130"></a>
<span class="sourceLineNo">1131</span>   * &lt;a href="http://en.wikipedia.org/wiki/Cartesian_product"&gt;Cartesian<a name="line.1131"></a>
<span class="sourceLineNo">1132</span>   * product&lt;/a&gt;" of the sets. For example: &lt;pre&gt;   {@code<a name="line.1132"></a>
<span class="sourceLineNo">1133</span>   *<a name="line.1133"></a>
<span class="sourceLineNo">1134</span>   *   Sets.cartesianProduct(<a name="line.1134"></a>
<span class="sourceLineNo">1135</span>   *       ImmutableSet.of(1, 2),<a name="line.1135"></a>
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<span class="sourceLineNo">1137</span>   *<a name="line.1137"></a>
<span class="sourceLineNo">1138</span>   * returns a set containing six lists:<a name="line.1138"></a>
<span class="sourceLineNo">1139</span>   *<a name="line.1139"></a>
<span class="sourceLineNo">1140</span>   * &lt;ul&gt;<a name="line.1140"></a>
<span class="sourceLineNo">1141</span>   * &lt;li&gt;{@code ImmutableList.of(1, "A")}<a name="line.1141"></a>
<span class="sourceLineNo">1142</span>   * &lt;li&gt;{@code ImmutableList.of(1, "B")}<a name="line.1142"></a>
<span class="sourceLineNo">1143</span>   * &lt;li&gt;{@code ImmutableList.of(1, "C")}<a name="line.1143"></a>
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<span class="sourceLineNo">1148</span>   *<a name="line.1148"></a>
<span class="sourceLineNo">1149</span>   * The result is guaranteed to be in the "traditional", lexicographical<a name="line.1149"></a>
<span class="sourceLineNo">1150</span>   * order for Cartesian products that you would get from nesting for loops:<a name="line.1150"></a>
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<span class="sourceLineNo">1160</span>   *<a name="line.1160"></a>
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<span class="sourceLineNo">1165</span>   *<a name="line.1165"></a>
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<span class="sourceLineNo">1277</span>   *<a name="line.1277"></a>
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<span class="sourceLineNo">1281</span>   *<a name="line.1281"></a>
<span class="sourceLineNo">1282</span>   * &lt;p&gt;&lt;i&gt;Performance notes:&lt;/i&gt; while the power set of a set with size {@code<a name="line.1282"></a>
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<span class="sourceLineNo">1287</span>   *<a name="line.1287"></a>
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<span class="sourceLineNo">1773</span>}<a name="line.1773"></a>




























































</pre>
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